User Manual

Control concept
Control concept and control blocks
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Status monitoring
[AO, BO, MO, AVAL, BVAL, MVAL]
The process is monitored via the feedback signal, and in the case of switching blocks, also via the ramp-up
and ramp-down parameters set in [TbTiDly]. If the feedback value deviates from the present value [PrVal]
and the delay in [TbTiDly] has not yet expired, the process is in a transitional state. The status monitoring
function shows the status at the transient state [TraSta] output. This output can be used to switch on any
subsequent components.
Feedback monitoring
[BO, MO]
Monitoring feedback may be based on a data point or a purely internal to the block based on the feedback
time parameter.
● Feedback data point available [FbAddr:] = Address
Monitoring is based on the feedback signals. The delays can be defined with the time parameters for
switch-on [TiMonOn], switch-off [TiMonOff] and open-circuit [TiMonDvn]. If the feedback signal
[FbVal] deviates from the output value [PrVal], an OFFNORMAL alarm will be triggered (provided the
alarm function is switched on).
● No feedback data point available [FbAddr:] = empty
Based on the feedback time parameter [TiMonOn/TiMonOff], the output [FbVal] is delayed by [PrVal].
The output [TraSta] signals transition state.
Alarm value monitoring
[AI, AO, AVAL, BI, BVAL, MI, MVAL]
Alarm monitoring is optional and can be enabled using [EnAlm]. Analog limit or switching values can be
monitored depending on the block type. The tolerance time [TiMonDvn] to trigger a process alarm can be
set. Deviations for switch on and off procedures can be distinguished for switching blocks.
Alarm monitoring can be enabled based on the process or time. You can switch off frost protection for
monitoring in summer e.g..
Reliability monitoring
[AI, AI_RED, AO, AO_RED, AVAL, BI, BI_RED, BO,BO_RED, BVAL, MI, MI_RED, MO, MO_RED, MVAL]
The blocks monitor the reliability of input and output sources and configuration errors. A system alarm is
generated, e.g., when a source no longer communicates and the cause is displayed on output [Rlb]. The
disturbance output [Dstb] changes to yes. This output, e.g., can return to the block for the local
disturbance to achieve a more secure position using a higher priority. Reliability monitoring can be
switched off using [OoServ], which may make sense for defective or faulty hardware.
Reliability monitoring is always active for the RED blocks since no [OaServ] is available. Superposed
control does not distinguish this state and plant safety is not provided under certain circumstances.
Minimum switching times
[BO, BVAL, MO, MVAL]
The minimum time on [TiOnMin] and the minimum time off [TiOffMin] may be defined to reduce switching
frequency. For a switch on or off command, is written to [PrioArr] as priority 6 and maintained there during
the defined switching period. No lower priority can change the switching value during this time frame.
Switch-on and switch-off delay
[BO, BVAL, MO, MVAL]
To delay switch on or off for elements [DlyOn/DlyOff], e.g., to implement a pump run-on to extract residual
heat. For a switch on or off command, the corresponding switching value is written to [PrioArr] as priority 6
and maintained there during the defined switching period. No lower priority can change the switching value
during this time frame.
Ramp-up/down time
Runtimes for ramp-up and down
[BO, BVAL, MO, MVAL]